Results of a proficiency test for multi-mycotoxin determination in maize by using methods based on LC-MS/(MS)

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M. Solfrizzo
A. De Girolamo
V.M.T. Lattanzio
A. Visconti
J. Stroka
A. Alldrick
H.P. van Egmond


maize, test-material, validation, z-score


Liquid chromatography coupled with single or tandem mass spectrometry (LC-MS/(MS)) is routinely used for the simultaneous determination of mycotoxins in food and feed although official methods using this technique have not yet been adopted by the European Committee for Standardization and the Association of Analytical Communities. A proficiency test (PT) was conducted for the simultaneous determination of up to 11 mycotoxins (aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), ochratoxin A (OTA), deoxynivalenol (DON), T-2 toxin (T-2), HT-2 toxin (HT-2), zearalenone (ZEA), fumonisin B1 (FB1) and fumonisin B2 (FB2)) in maize using LC-MS/(MS) to benchmark laboratories currently using this technique and to obtain information on currently used methodologies and method-related performances. Each participant received the following: instructions; a comprehensive questionnaire; a mixed mycotoxins calibration solution; a spiking solution (AFB1, AFB2, AFG1 and AFG2, OTA, DON, T-2, HT-2, ZEA, FB1 and FB2); and two test materials, namely a contaminated maize sample and a blank maize sample to be spiked with a spiking solution containing 11 mycotoxins. Laboratory results were rated with z-scores. Of the 64 laboratories enrolled in the PT, 41 laboratories from 14 countries returned 43 sets of results for various combinations of analytes. The majority of laboratories (61%) reported results for all 11 mycotoxins, whereas the remaining laboratories reported results for a restricted combination (from 2 to 10 analytes). For contaminated maize and spiked maize the percentage of satisfactory z-score values (|z| ?2) were: DON 55% and 49%, FB1 50% and 30%, FB2 52% and 38%, ZEA 68% and 64%, T-2+HT-2 toxins 82% and 85%, OTA 58% and 60%, AFB1 56% and 62%, AFG1 73% and 84%, AFB2 40% and 78%, AFG2 64% and 78%, respectively. The poorest performance (|z| >3) was obtained for FB1 (31%), FB2 (32%), AFB1 (32%) and AFB2 (32%) in contaminated maize and for DON (35%), FB1 (63%) and FB2 (52%) in spiked maize. Mean recovery results were acceptable for all mycotoxins (74% to 109%), except for fumonisins, where these were unacceptably high (159% for FB1 and 163% for FB2). A robust and reliable method for simultaneous determination of 11 mycotoxins in maize could not be identified from the results of this PT. Additional experimental work is necessary to set up a method suitable for inter-laboratory validation. The results of this PT and the relevant method's details can be useful to identify methodology strengths and weaknesses.

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Council for Agricultural Science and Technology (CAST), 2003. Mycotoxins: risks in plant, animal, and human systems. Task Force Report No. 139. CAST, Ames, IA, USA, 199 pp.
Commission of the European Communities, 2006. Commission Regulation (EC) No. 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. Official Journal of the European Union L364: 5-24.
European Committee for Standardization (CEN), 2010. Foodstuffs - determination of aflatoxin B1 in cereal based foods for infants and young children - HPLC method with immunoaffinity column cleanup and fluorescence detection. EN 15851:2009. BSI, London, UK, 18 pp.
Entwisle, A.C., Williams, A.C., Mann, P.J., Slack, P.T. and Gilbert, J., 2000. Liquid chromatographic method with immunoaffinity column cleanup for determination of ochratoxin A in barley: collaborative study. Journal of AOAC International 83: 1377-1383.
Kunsagi, Z., Ambrosio, M., Breidbach, A. and Stroka, J., 2010. Determination of ochratoxin A in cereals, green coffee, paprika and test solution. Report on the 2010 proficiency test of the European union reference laboratory for mycotoxins, for the network of national reference laboratories. JRC Scientific and Technical Reports, Brussels, Belgium, 57 pp.
Lattanzio, V.M.T., Solfrizzo, M. and Visconti, A., 2009. Enzymatic hydrolysis of T-2 toxin for the quantitative determination of total T-2 and HT-2 toxins in cereals. Analytical and Bioanalytical Chemistry 395: 1325-1334.
MacDonald, S.J., Anderson, S., Brereton, P., Wood, R. and Damant, A., 2005a. Determination of zearalenone in barley, maize and wheat flour, polenta, and maize-based baby food by immunoaffinity column cleanup with liquid chromatography: interlaboratory study. Journal of AOAC International 88: 1733-1740.
MacDonald, S.J., Chan, D., Brereton, P., Damant, A. and Wood, R., 2005b. Determination of deoxynivalenol in cereals and cereal products by immunoaffinity column cleanup with liquid chromatography: interlaboratory study. Journal of AOAC International 88: 1197-204.
Miller, J.D., 2008. Mycotoxins in small grains and maize: old problems, new challenges. Food Additives and Contaminants: Part A 25: 219-230.
Shephard, G.S., Berthiller, F., Burdaspal, P.A., Crews, C, Jonker, M.A., Krska, R., MacDonald, S., Malone, R.J., Maragos, C., Sabino, M., Solfrizzo, M., Van Egmond, H.P. and Whitaker, T.B., 2012. Developments in mycotoxin analysis: an update for 2010-2011. World Mycotoxin Journal 5: 3-30.Shephard, G.S., Berthiller, F., Burdaspal, P.A., Crews, C., Jonker, M.A., Krska, R., Lattanzio, V.M.T., MacDonald, S., Malone, R.J., Maragos, C., Sabino, M. Solfrizzo, M., Van Egmond, H.P. andWhitaker, T.B., 2013. Developments in mycotoxin analysis: an update for 2011-2012. World Mycotoxin Journal 6: 3-30.
Solfrizzo, M., Alldrick, A.J. and Van Egmond, H.P., 2009. The use of mycotoxin methodology in practice: a need for harmonization. Quality Assurance and Safety of Crops & Foods 1: 121-132.
Solfrizzo, M., De Girolamo, A., Gambacorta, L., Visconti, A., Van Egmond, H.P. and Stroka, J., 2011. Determination of fumonisins B1and B2 in corn based foods for infants and young children by LC with immunoaffinity column cleanup: interlaboratory validation study. Journal of AOAC International 94: 900-908.
Thompson, M., 2000. Recent trends in inter-laboratory precision at ppb and sub-ppb concentrations in relation to fitness for purpose criteria in proficiency testing. Analyst 125: 385-386.
Thompson, M., Ellison, S.L.R. and Wood, R., 2006. The international harmonized protocol for the proficiency testing of analytical chemistry laboratories. Pure and Applied Chemistry 78: 145-196.
Visconti, A., Lattanzio, V.M.T., Pascale, M. and Haidukowski, M., 2005. Analysis of T-2 and HT-2 toxins in cereal grains by immunoaffinity clean-up and liquid chromatography with fluorescence detection. Journal of Chromatography A 1075: 151-158.